I successfully installed El Capitan 10.11 on my MacBook Pro (running 10.10) inside of VirtualBox 5.0.8 r103449. Everything works pretty well and the performance is quite reasonable for a virtual machine.

One issue remaining is that my resolution is fixed at 1024x768. With my Windows and Linux guests, installing the VBox Guest Additions resolves this very easily.

The supplied VBOX Guest Additions ISO has guest installation utilites for Windows, Linux, Solaris, and OS2, but lacks guest additions for OSX. Does VirtualBox provide any guest additions for El Capitan guests (running on Mac hardware)? Or is this part of the roadmap at all?

Ultimately I'm trying to resolve my resolution issues, so if anyone has suggestions for that with El Capitan, please let me know.

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